When I learned about trees as a kid I had an idea to make a forum/textboard with nodes.
When you enter the site you see the top node and when you click on it the sub the all the connected nodes get opened. If you click on these nodes their connected nodes open and so on. A bit like a mindmap.
I never implemented it because I thought it would scare off users and never get enough data to be interesting. It probably was an excuse because I'm lazy and I would've been hard with my skillset then.
I'll probably won't pick it up, but in my mind it's cool. You have a big mindmap where you can zoom out and see all your interest in one frame.
eg all-technology-programming-win32-graphics all-news-europe-information law
I still don't think it'll work, mainly because categorizing information is impossible. You might be interested in graphics so you read all-technology-programming-win32-graphics but you're missing out on all the info on all-technology-programming-3dgraphics
I think this is why textboard style information reigns supreme. I hardly read any specific mailing lists and all the good ones I'll never find because I don't know they exist.
Maybe all-technology-programming-gdifreakz is where all juicy general purpose 3d graphics info gets posted because all the cool kids are hanging out there.